In an office environment are documents each having a different size. The documents are generally bound into files or books and are stored on desks or in cabinets.
In private companies, paper having a size of A4 or A3 is often used, but in government and public offices size B paper is relatively often used partially because use of size B paper is required by law or other regulations such as ministry ordinances. As a result, size A paper and size B paper coexist there. This is a cause for generation of a big problem in storage and management of documents.
Recently because of the circumstances as described above, a plan for unification of document sizes in government and public offices has been undergoing. Accordingly, sizes of documents to be prepared anew in the future can be unified according to a new rule.
However, documents already prepared have been stored as original documents each having a size B (for instance, a size of B5), if a copying machine is used to make a copy of an original document having a size of B5, excluding a case where it is required to enlarge or reduce a size of the document, generally copying is executed on recording paper having a size of B5.
On the other hand, there is a copying machine having a function to detect a size of a document, automatically select recording paper having a size suited to the document from a paper feed cassette and send out the paper, but it is difficult to insure copying on recording paper having a unified size (for instance, size A4) in the copying machine as described above. Even in a copying machine not having the function as described above, if various types of recording paper having a different size respectively are set therein, the possibility for a user to select recording paper having the same size as that of an original document is very high, so that it is difficult to execute copying on recording paper having a unified size. For this reason, in order to insure unification of sizes of recording paper into a unified one in an office, it is necessary to use a copying machine which allows only recording paper having a specified size to be set therein.
However, if this type of copying machine is used, there occurs no problem when a document having a size smaller than A4 is copied, but a document larger than size A4 can not be copied with the same size, which is inconvenient. For this reason, when it is required to copy a document having a size larger than A4 with the same size, it is necessary to record a sheet of document on two sheets of recording paper making use of a cross-page continuous copying technique.
When using the cross-page continuous copying technique, if it is tried to copy, for instance, a document 4901 having a size of A3 larger than A4 onto two sheets of recording paper 4902, 4903 each having a size of A4 as shown in FIGS. 27 (a), (b), an image of the document 4901 is simply divided ibto two portions and recorded on each sheet of recording paper as shown in FIG. 27 (b).
However, and with reference to FIG. 28, with a copying machine in which the conventional type of cross-page continuous copying technique is simply applied, when dividing and recording a size A3 document to two sheets of size A4 recording paper, there occurs no specific problem, but when a size B4 document 4002 is placed on a document mount 4001 for copying it onto recording paper having a size of A4, reproducibility of the document image is disadvantageously degraded.
Concretely the document 4002 is divided at the center thereof into two portions 4002a, 4002b each having a size of B5. As shown in FIG. 28 (b), these images are positioned substantially at centers 4005a, 4005b of two sheets of size A4 recording paper 4003a, 4003b respectively and recorded as images 4004a, 4004b. When these two sheets of recording paper 4003a, 4003b are filed so that the image surfaces face to each other, as shown in FIG. 28 (c), a portion excluding bound sections 4006a, 4006b can be seen as a spread image having a size substantially equal to A3. However, the original image R is changed into one cut at the center, so reproducibility of the original image is disadvantageously lost.
Next, as a conventional type of image recording apparatus, there is the one as shown in FIG. 29 having a sort function as well as a stable function which sorts recording paper with image data recorded thereon with a sorter and binds bundles of sorted recording paper into a book with a stapler.
This image recording apparatus largely comprises an automatic document feeder 4301 which automatically feeds a document, an image reader 4302 which reads image data from a document fed by the automatic document feeder 4301, an image forming section 4303 for recording read image data on recording paper, a sorter 4304 which sorts recording paper discharged from the image forming section 4303 and stores the recording paper in a plurality of bins 4304a, and a stapler 4305 which binds bundles of recording paper stored in the bins 4304a of the sorter 4304 with a staple. It should be noted that the stapler 4305 can move in the direction 4305a along the bin 4304a and also can move in the direction 4305b in which the bins 4304a is moved up and down.
When using the staple function in the apparatus as described above, a user at first selects a staple function through an operation displaying section (not shown), then selects actuation of the sorter 4304, sets a width for a binding space for binding recording paper, and then presses down a Copy Start key (not shown), thus a bundle of recording paper bound with staples being obtained.
Herein a binding space width is set to prevent the state where output image data on recording paper becomes hard to read (or hard to see) when bound with staples. In other words, as shown in FIG. 30, a region which may become hard to read depending on a position of a staple 4401 is set as a binding space width .alpha.. Concretely the binding space width is set by inputting a value with a unit of mm or by selecting a desired value from a plurality of binding space width values set previously. On the other hand, an image recording apparatus records an original image displacing a recording position of image data on recording paper by a value corresponding to the set binding space width .alpha..
It should be noted that, in the conventional type of image recording apparatus, as the stapler 4305 moves in the direction 4305a along the bin 4304a as well as in the direction 4305b in which the bin 4304a is moved up and down as shown in FIG. 29 and a direction in which stapling is possible on recording paper stored on the bin 4304a is specified (fixed) previously, if it is necessary to set a staple position d or instance on a transverse edge of size A4 recording paper or a vertical edge of size A4 recording paper, when placing a document 4501 on the automatic document mount 4301 as shown in FIG. 31 (a), the document 4501 is placed to obtain a desired stable position referring to a mark 4502 indicating the staple direction.
If a document having a size of A4 shown in FIG. 31 (a) is placed in the transverse direction, the recording paper is bound at a staple position shown in FIG. 31 (b). If the document 4501 having a size of A4 is placed in the vertical direction on the automatic document feeder 4301, the recording paper is bound at a staple position shown in FIG. 31 (c).
Although a plurality of sheets of recording paper can be bound into a book by using the image recording apparatus as described above, an expensive stapler is required, so that many users generally bind recording paper using a hand stapler after recording paper is outputted from an image recording apparatus not having a stapler.
However, with the conventional type of image recording apparatus having a staple function as described above, when binding recording paper into a book with the staple function, a user must at first select a staple function, then select actuation of a sorter, and furthermore set a width of a binding space required when binding recording paper, so that complicated operations are required and in addition the operability is rather poor.
In addition, although binding can be executed at a desired staple position by taking necessary measures to achieve an appropriate mounting direction of a document when placing the document on the automatic document feeder, sometimes a user may overlook a mark indicating a staple direction (as indicated by the reference numeral 4502 in FIG. 31), or may place a document inappropriately without understanding meaning of the mark, or may set a document in a wrong outing direction, and then a result of binding may become an unexpected one, or a large quantity of wrong and unnecessary copies may be generated, and furthermore extreme carefulness is required to users when placing a document, which is inconvenient.
Also with the conventional type of image recording apparatus having a staple function as described above, when bound into a book, an image on the first or final page can be seen up to the border with a binding section as shown in FIG. 32 (a), but an image on each of intermediate pages can not be seen up to the border with the binding section as shown in FIG. 32 (b), and for this reason if it is assumed that an image which can be seen on the first page (1) and second page (2) in FIG. 32 (a) is that shown in FIG. 33 (a) and that an image which can be seen on the ninth page (9) and tenth page (10) in FIG. 32 (b) is that shown in FIG. 33 (b), there occurs a difference in size between FIG. 33 (a) and FIG. 33 (b) although the difference is slight, and the more a number of pages to be bound, the larger this size difference is, which makes it hard to see a spread image at a position near the binding section.
It should be noted that, although a continuous image (letter "A") is shown as an example on the right and left pages in FIG. 33, the same is true even if images on the right and left pages are different ones.
On the other hand, a user not having the conventional type of image recording apparatus with a staple function binds recording paper by using a hand stapler, and in that case the user binds recording paper deciding a staple position depending on his or her feeling, so that, when recording paper is bound into a plurality of books, staple positions are not aligned and the appearance is rather poor.
Also when bound recording paper is punched and filed in a binder or the like, sometimes a staple position overlaps a punch hole, which may cause the necessity of removing staples and lower the workability.
Also prepared copies are often bundled, and a bundle is bound with such a tool as a stapler. Herein it is assumed, for instance, that there are sheet documents G.sub.1 to G.sub.N each having a size of B4 as shown in FIG. 34, and that there are different images in the right and left section of each sheet document. For convenience of description, these images are paged (1) to (2N). Namely images (1), (2) each having a size of B5 are formed in a first document G.sub.1, while images (3), (4) each having a size of B5 are formed in a second document G.sub.2. When these document are copied, the prepared copies are finally arrayed as shown in FIG. 35 and are bound into a book. In one side of each recording paper is formed an image having an odd page number, while in another side of each recording paper is formed an image having an even page number respectively. In this figure, when the recording paper is bound at the left edge section, in each page of recording paper is shown an image according to an order of pages. When a first page of a bundle of recording paper bound is opened as shown in FIG. 36 (a), the images (1), (2) are shown in a spread form, so that the document G.sub.1 is reproduced. Similarly, when an intermediate section is opened as shown in FIG. 36 (b), for instance images (9), (10) are shown on the right and left pages.
By the way, when binding recording paper as described above, it is known that a binding space must be formed previously during the recording step. Generally a binding space for copying is maintained at a constant width during a copying operation, but it can be adjusted by an operator prior to a start of a copying operation. Also the binding space shown in FIG. 36 is formed as described above.
With the conventional technology as described above, however, when recording paper is bound into a book, an image on the first or final page can be seen up to the border with the binding space as shown in FIG. 36 (a), but an image on any intermediate page can hardly be seen up to the border with the binding space as shown in FIG. 36 (b), and if it is assumed, for instance, that an image which can be seen in a state shown in FIG. 36 (a) is that shown in FIG. 37 (a) and that an image which can be second in a state shown in FIG. 36 (b) is that shown in FIG. 37 (b), there occurs a size difference between the image shown in FIG. 37 (a) and that shown in FIG. 37 (b) although the difference is slight, so that the more a number of pages to be bound is, the larger the size difference is, and when seen as a spread image as shown in FIG. 37, the image is extremely hard to see.